Field of the Invention
The present disclosure relates to a failure detection apparatus of a Motor Drive Power System (MDPS). More particularly, the present disclosure relates to a detection apparatus and detection method to determine the failure and the type of failure of the MDPS by monitoring the whole state of a vehicle.
Description of Related Art
As in-vehicle parts are digitalized, concerns over the functional safety of a vehicle increase, and International Standards ISO26262 about the functional safety of a vehicle is drawing attention from vehicle-related manufacturers.
In regard to a Motor Drive Power System (MDPS), more efforts to provide a steering apparatus meeting ISO26262 have been made. As limitations that may occur in the MDPS, there are over steering and wrong direction. Over steering refers to a phenomenon that the vehicle body excessively turns compared to the steering angle, and denotes a phenomenon that can occur when the rear wheel loses a grip force by sliding outwards. Also, wrong direction refers to a phenomenon that the vehicle body travels in a different direction from the steering angle of a steering wheel, and denotes a phenomenon that a vehicle runs in a different turning direction from a request of a driver.
FIGS. 1 and 2 show over-steering and wrong direction during the turning of a vehicle.
In the drawings, a vehicle starts to drive, and starts to turn. Also, when a failure occurs in the MDPS, a vehicle cannot normally turn a corner, and runs on an abnormal path.
Accordingly, when a failure occurs in the MDPS during driving, a vehicle cannot turn a corner according to a request of a user and spins out of a road inwards or outwards.
As a related art, Korean Patent Application No. 10-2012-0092310 (Hereinafter, referred to as Document 1) discloses a technology of securing straightness of a vehicle even when a rear wheel steering apparatus of a vehicle breaks down, by steering the front wheel of a vehicle in the same direction as the rear wheel using a front wheel steering apparatus of a vehicle.
However, since a technology of detecting a failure of an electronic steering apparatus of a vehicle in early stage and blocking application of a current to a motor to enable the manual operation of the steering apparatus is not disclosed in Document 1, the drivability of a vehicle cannot be maintained when the steering apparatus breaks down.
Also, the steering apparatus needs to be reset and reoperated due to the failure of the MDPS, and a method of preventing the occurrence of a failure is not provided.
The information disclosed in this Background of the Invention section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.